That was a great and precise reply!
First, I didn't mean we are allowed to go on looking at women and lust on them. What I meant is that if, by chance, you met a woman, and then went home, and thought about her in a sexual way. This is not wrong in Islam. But you should stop here. Further actions like masturbating or sexual harassment is not right in Islam.
I fail to understand why many religions prohibit masturbation. If that's to encourage marriage it's plausible, but most married men used to masturbate before marriage, so masturbation is not a substitution for marriage. You stress on the point that by masturbating to a woman you're like raping her because she wouldn't have allowed you to copulate with her. Well, that's an unproven philosophical hypothesis. Who knows, may be she would have gave you permisssion if you asked her. May be she just wouldn't care. She's out of your physical world. She's just in your imagination. You're not hurting her in any way. In fact, you're hurting yourself if you ignore your sexual urges. It's as if you're hungry, but you won't eat for a philosophical reason, like "Shouldn't I give this food to the poor? If I ate it, then I'd be a thief, therefore I won't eat it, and I'll remain hungry.". Now, neither you nor the poor got the food. You'll tell me we really should offer help to the poor, which is undoubtedly right, but you can't feed every single poor person in the world, not even in your state. What I meant by this indirect example is that you shouldn't keep yourself within philosophical restraints. In my opinion, unless a person does physical or psychological harm to another person, they are not guilty. You are not harming the women you think about while you masturbate in any way.
By the way, later Islamic preachers have allowed masturbation. And others allowed masturbation in case one's sexual urge is very high that they would be committing rape if their sexual urges had not been fulfilled.
Masturbation to me is a natural temporary way to fulfill my sexual needs until I get married. Without unleashing this need in form of masturbation (or other sexual relationships which I do not approve of), I'm sure I'd be very psychologically distressed.
Many people do not masturbate and they're living with it normally. For me, it'd be very difficult, and I don't even think I need to try quitting, because I don't think it's wrong in the first place. Smoking is harmful. Sexual relationships get you STDs. But masturbation is really clean from a practical and scientific points of view.